This invention relates to disposable applicators suitable for use by trained personnel in hospital or other institutional environments; by untrained persons at home, both for self-administation and for use on small children; and for use by those having severe restrictions on their freedom of movement. It has important benefits in the prevention of disease transmission, in reducing a serious and increasing health hazard to health professionals, in reducing the risks of injury to small children, and in helping the handicapped live independently.
Insofar as applicants can determine, there are no disposable suppository applicators on the market today, and certainly none in widespread use. Due to the costs and uncertainties of sterilization procedures, there likewise appear to be no applicators on the market intended for repeated use. Indeed, in the present state of the health care industry, it is virtually certain that no such applicators would be used repeatedly by health care personnel, even if they were available. The industry has, instead, turned to other means of providing protection for its personnel, primarily the latex glove.
However, use of the latex glove has proved in practice to be far from the panacea originally envisioned by health care planners. It has long been known that even an apparently perfect latex glove can have minute openings too small to be seen by the human eye yet large enough to allow the HIV or other virus molecules to pass through. In May of 1988, the National Institute for Occupational Safety and Health issued a report on the effectiveness of rubber latex gloves as a barrier to human immuno-deficiency virus in which it stated that it was evident that standard medical rubber latex gloves are ineffective in providing reliable barriers against many pathogens, and that plastic medical gloves were no better. The NIOSH report further pointed out that the prevalence rate for AIDS cases with no identified cause among health care workers was nearly twice the rate among all other AIDS patients. As the possibility of transmission of and infection by such viruses becomes more widely known, more and more health care workers are turning to the use of double pairs of latex gloves, as recommended by the CDC. However, not only does this double the cost of such prophylactic measures, but even this extreme step can still fail to adequately protect the wearer, and the use of latex itself can actually cause its own unique problems.
Being a natural product, the latex in such gloves can and all too often does cause allergic reactions. The American College of Allergy, Asthma and Immunology has estimated that at least as many as eight to seventeen percent of all health care workers are latex-sensitive; others have estimated that as many as one in five may exhibit various degrees of sensitivity to the natural protein comprising latex. The range of allergic reactions runs from skin rash, hives, intense itching, swollen eyes, runny noses and sneezing to asthma-like symptoms including wheezing, coughing and shortness of breath, and can progress to inflamed mucous membranes and closed airways as anaphylactic shock develops.
Several deaths have been confirmed among health care workers to have resulted from latex allergies, and the Food and Drug Administration has reported at least sixteen deaths due to anaphylactic shock caused by allergic reactions to but one type of latex devices, enema catheters.
Many health care professionals have formed the opinion that the powder commonly employed in latex gloves to make it easier to don and doff the gloves, particularly after perspiring, is the primary cause of such problems. According to this theory, some of the natural protein molecules in the latex glove bind to the powder, and the protein-based powder then becomes airborne when the gloves are removed, where they are subsequently inhaled by the workers. At least one state, Oregon, has considered statutorily banning the use of all powdered latex gloves in health care facilities.
However, not even powder-free latex gloves can solve the problem which applicants' present invention solves, nor so conveniently. The FDA, in June of 1996, issued a Public Health Advisory to the effect that not only could large quantities of non-powdered, chlorinated latex gloves spontaneously ignite in warehouse conditions, but that merely exposing the gloves to warmer temperatures could cause the latex to deteriorate and lose its effectiveness as a barrier. And, of course, even an apparently perfect, non-powdered latex glove can still have microscopic pores large enough to permit the passage of even the relatively large HIV virus.
It is thus apparent that a serious medical problem exists for health care providers in the aggregate, and has been known to exist for quite some time. It is also apparent that the industry is in urgent need of devices such as applicants' which eliminate a major need for doubled latex gloves while positively preventing the transmission of disease.
Various types of devices are known to the art for implanting different kinds of materials or fluids into the body, but which for various reasons do not accomplish the purposes of the present invention. The type of devices known as catheters generally are, comparatively speaking, very expensive devices whose relatively high cost can be justified either by the worth of the procedure or by a replacement cost sufficiently great to justify the cost of sterilization for re-use. Further, devices of this type typically are little more than elongated, flexible, covered hypodermic needles intended to be threaded up a vein or artery to deliver the material or fluid to a pre-selected location far removed from the point of entry. U.S. Pat. No. 4,900,303 to Lemuelson may be representative of this class. Lemuelson--and other catheter patents--disclose little of interest for the purposes of this invention beyond finger rests for control and plunger mechanisms for dispensing the materials or fluids.
The class of devices known as sample collecting devices, although intended for a purpose opposite that of the present invention, may be considered intermediate between catheters and the present invention. Generally, such devices are not intended for sampling at locations so far removed from the point of insertion, and recently a sub-class of such devices intended for self-use has appeared. U.S. Pat. No. 4,877,037 to Ko and Fanselow, and the patents disclosed therein, may be representative of this class. Ko discloses a washerlike guard means slideably adjustable among an unlimited number of positions along a protective sleeve, and necessarily relies upon a precise relationship of sizes to permit the precisely desired, tight frictional fit. Ko also discloses a separate stop means which may be a discrete piece also relying on a precise frictional fit or in at least one embodiment may be formed integrally with its respective tube at one specific position. Being intended for single uses and to eliminate the costs of trained medical personnel, such devices can in general be both more precisely made and more expensively made than can devices which are made for the purposes of the present invention.
U.S. Pat. No. 939,693 to Holtzmann discloses a device also intended for placement of suppositories and bulk `semiplastic` medicaments. The Holtzmann device comprises a slotted outer tube with a flat-surfaced or washer-like flange rigidly attached to its outer end, an inner tube open at both ends and telescopically slidable within the outer tube, and a piston interior to the inner tube. The end of the outer tube opposite the open end is operably closed by a threaded plug mating with oppositely-machined threads on the interior side of the outer tube, and a pin or screw is attached at one end to the inner tube and projects through the slot in the outer tube and is attached at its other end to a slidable ring or sleeve encircling the outer tube. Use of the device is described as requiring two hands to extend the inner tube into position for receiving either medicaments or discrete suppositories; after placement, a suppository is dispensed in another two-handed operation by holding the outer tube and flange stationary with one hand while withdrawing the inner tube with the other hand by means of the slidable sleeve, during the course of which the stationary piston prevents the suppository from remaining inside the inner tube. The disadvantages of such a complicated device are readily realized: prohibitively expensive for today's manufacture for single usages; impossible to (economically) sanitize for repeated usages; and two-handed operations required both to initially adjust the device to receive a suppository and to dispense the suppository. Thus devices of this type are incapable of achieving the purposes of this invention.
Italian Patent No. 580,657 represents yet another approach. Like Holtzmann, it too has an outer tube with a threaded end cap, although with such on the outer rather than the inner surface of such tube. The outer tube has an integral, fixed position flange, undoubtedly serving as a rest or stop. As shown in the drawings, the end-cap is formed with an enlarged rim and a central orifice for receiving a plunger connected at its exterior end to a relatively large disc and at its other end to a moveable piston inside the outer tube. From the drawings, operation would appear to require forcing a portion of a suppository into the open end, thereby leaving most of the suppository exposed during insertion, permitting premature melting, breakage and associated difficulties. Although actual dispensation may be accomplishable with one hand, presumably with two fingers on the far side of the enlarged rim of the end cap and a thumb on the opposite side of the plunger disc, such a device obviously has some of the same disadvantages as the Holtzmann-type devices, namely, expense of manufacture and difficulty and cost of sterilization, as well as the additional disadvantage of inability to protect suppositories during the insertion process.
Since none of these prior devices appears capable of solving the problems solved by the present invention, it is not surprising to see that apparently neither of these types of devices is on the market today, nor, for that matter, to the best of applicant's ability to ascertain, is any other suppository insertion device, of any kind. Thus, despite the accentuated need caused by the extreme problems of AIDS and latex allergies and reactions, the longstanding need for a product such as applicant's remains unfilled. In addition, should the present invention be widely adopted, then numerous instances of latex reactions and of disease transmissions will have been prevented.